Electronic circuits, including electronic circuits formed as integrated circuits on semiconductor substrates, include various active and passive components. Passive components may include resistors designed to have different resistances in different circuits according to their function. In some cases, a resistor may have a resistance that is different from its designed resistance, e.g. because of process variations across a semiconductor substrate, from substrate to substrate, or other effects. Different circuits may have different ranges for acceptable resistances and in some cases process related variation may impact circuit performance. It is desirable, therefore, to provide a circuit that overcomes or reduces the impact of such process variations.